Combustion-engine valve.



G. FORNACA.

comsusnou ENGINE VALVE: APPLlCATlON FILED JULY 20.1916.

1,25 1,003. Patefited Dec. 25, 191 7.

w W Z 6., zwwi Fluounl'o:

UNITED STATES PATENT OFFICE.

GUIIDO common, or TURIN, ITALY, ASSIGNOR T0 1*. I. A. 'r., or POUGHKEEPSIE, NEW

YORK, A CORPQRATION on NEW YORK. c i

COMBUSTION-ENGINE VALVE.

Specification of Letters Patent. Patgnfed Dec, 25, 1917.

Application filed July 20, 1916. Serial No. 110,298.

To all whom it ma? concern:

Be it known t at I, Goino FORNACA, a subject of the King of Italy, residing at Turin, in the Province of Piedmont, Italy, have invented certain new and useful Improvements in Combustion-Engine Valves, of which the following is a full, clear, and exact specification.

This invention relates to improvements in combustion engine valves, and has particular reference to improved means for mounting a puppet valve in the valve stem guide of a combustion engine, whereby not only can the valve be readily taken out for replacement or repair, but also enabling the valve stem bushing to be more easily replaced than is at present the case.

Puppet valves are subject to a great deal of wear in the valve stemguide, and it is a matter of considerable difliculty at the present time to take such valves out owing to the necessity of relieving the spring compression and then of disconnecting the valvefrom its guides. valve spring ordinarily bears against a portion of the casting and the lower end against the washer which is )inned to the valve stem, and one object of this invention is to dispense with the use of pins passed through the valve stem and at the same time enable the lower spring seat to be quickly disconnected from the valve stem. A further ob ject of the invention is to enable the valve stem bushing to be readily replaced from below instead of from above according to the common practice.

The invention with reference to a preferrcd form thereof is shown in the accompanying. drawings, in which- Figure 1 is a vertical section, and

Fig. 2 is a section on the line 2-2 of Fig. l.

1 represents an engine cylinder, 2 the piston, 3 the connecting rod, 4 the explosion space connected to the valve chamber 5, and 6 is the usual chamber outside the valve connected either to the inlet or to the exhaust in the usual manner. 8 represents a valve generally of the mushroom type which closes on seat 9, and 10 is an opening to receive a plug through which the valve can be inserted and removed. 11 is the valve stem which slides in the valve stem support 12, and 13 is a bushing which is inserted between the The upper end of the valve stem 11 and-the valve stem support 12. 14 is a valve spring which is held under compression between the upper collar 15 which is carried by the bushing 13 and a lower collar 16 which is carried by the lower end of the valve stem l1. 17 is the tappet which operates the valve, the mounting of the tappet, the cam, etc., being omitted herein because well known and not necessary to a full understanding of this invention.

The lower collar 16 instead of being pinned to the valve stem as in the ordinary construction is, according to this invention,

"attached thereto by a self locking key construction which dispenses with the necessity of drilling a hole through the valve stem to receive the pin. In this invention the valve stem is provided with a plurality of shoulders 19 of about the same diameter as the valve stem so. as topass through the bushing. 20 is a conical key formed in two or more sections having interior shoulders- 21 which interlock .withthe circumferential shoulders 19 on the'valve stem. The lower collar 16 is providedwith an internal conical'surface 22 which comprises the blocks 20 on the valve stem. 23 is a split clamping ring for holdingthe block sections 20 on the valve stem before the collar 16 is seated on the key blocks 20 when the spring is let go.

The upper end of the spring is held under the collar 15, and this collar 15 .is within the sleeve and slides on the bushing until stopped by the beveled shoulder 26. The beveled shoulder 26 preferably abuts against the lower side of the valve stem support 12.

In assembling, the bushing 13 will be inserted from below in the valve stem guide 12, and the valve and stem will be inserted through opening 10 from above. Collar 15 will then be slid on to the bushing, then the spring, and then the lower collar 16. A suitable tool will then bevapplied to compress the spring between the stationary collar 15 and collar 16 sufficiently so that the key blocks 20 can be positioned and clamped to the valve stem by the ring 23. Then the compression of the spring is relieved and the collar 16 seats itself on the key blocks 20 and thereafter holds the lower end of the spring under the desired compression necessary to close the valve quickly.

It is to be understood that the invention is not restricted to the particular form of engine shown herein, but is applicable to puppet Valves in various types of engines, such as overhead valves, etc., and various modifications and changes may be made in the detailed construction herein shown without departing from the scope of the appended claims.

Having thus described my invention I declare that what I claim as new and desire to secure by'Letters latent, is

1. An engine cylinder having a valve stem guide, a puppet valve stem sliding therein, a shouldered bushing for said valve stem, a tapered spring collar fitting on said bushin and engaging said shoulder, a separable key interlocking with the lower end of the valve stem, a ta ered spring collar engaging and holding said key interlocked with said valve stem, and a valve spring between said collars.

2. In a combustion engine valve mechanism, the combination with a puppet valve having a stem, of a valve stem guide comprising a valve support and a bushing sleeve inserted between said support and said stem, a shoulder on said sleeve engaging the end of said support to hold said sleeve against inward movement and having an outwardly tapered exterior surface, an inner spring collar having a recess fitting the taper off said shoulder, a key interlocking with the valve stem and having an inwardly tapered exterior surface, an outer spring collar having a recess fitting the taper of said key and an expansible spring held between said collars and pressing them in opposite directions menace to aline them on their respective tapers and accurately center the spring.

3. A valve spring holding means comprising a valve stem, a series of rounded grooves and ridges on said stem, a sectional split key having an inwardly tapered exterior surface and an inner face formed to fit the grooves and ridges on said stem, a spring holder having an inner tapered recess fitting the exterior ens-face of the key sections and locking them in place on the stem, guiding means for the valve stem having an outwardly tapered shoulder, a second spring holder having a tapered recess fitting the taper of said shoulder and a valve spring between said holders pressing them in opposite directions to accurately centered seats on said tapered shoulder and key.

4. In valve mechanism for a combustion engine, the combination with valve guiding means and a valve spring for holding the valve against its seat, of valve spring holding means comprising op ositely directed conical surfaces carried 1 y the guiding means and the valve stem respectively, valve spring collars having inner conical recesses accurately centered on said conical surfaces by the expansion of said spring, and oppositely tapered exterior surfaces on said valve collars for accurately alining the opposite ends of the spring. 7

In testimony whereof l aiiix my signature, in presence of two witnesses.

GUIDO FGRNACA.

Witnesses CAVALL CABLE, CARLO Mnssmro Geneva. 

